Abstract

The eclipsing nova-like cataclysmic variable star V348 Pup exhibits a persistent luminosity
modulation with a period 6 per cent longer than its 2.44-h orbital period (Porb). This has been
interpreted as a `positive superhump' resulting from a slowly precessing non-axisymmetric
accretion disc gravitationally interacting with the secondary. We find a clear modulation of
mid-eclipse times on the superhump period, which agrees well with the predictions of a
simple precessing eccentric disc model. Our modelling shows that the disc light centre is on
the far side of the disc from the donor star when the superhump reaches maximum light. This
phasing suggests a link between superhumps in V348 Pup and late superhumps in SU UMa
systems. Modelling of the full light curve and maximum entropy eclipse mapping both show
that the disc emission is concentrated closer to the white dwarf at superhump maximum than
at superhump minimum. We detect additional signals consistent with the beat periods
between the implied disc precession period and both 1
2 Porb and 1
3 Porb: